1. Field of the Invention
The invention relates to a heat-dissipating fan, and more particularly, to a heat-dissipating fan suitable for use in an electrical appliance such as a personal computer.
2. Description of the Related Art
As the performance of technical devices such as an electric appliance progresses, issues related to heat dissipation in highly integrated devices are more critical. FIG. 1 is a cross-sectional view of a motor 7 of a conventional heat-dissipating fan. The motor 70 includes an axle 70, a bearing 71, a rotor 72 and a stator 73. The axle 70 is made of stainless steel, located at a central location of the rotor 72. A magnetic bar 74 is mounted on a side of the rotor 72. The bearing 71 is located at a central location of the stator 73. The stator 73 is further provided with a silicon steel sheet 75. The axle 70 of the rotor 72 penetrates the bearing 71 of the stator 73. The axle 70 has an oil guide 76 at its upper end and a C-shaped fastener 77. After electrical power is supplied, lines of magnetic force are produced between the rotor 72 and the stator 73 to drive the motor 7 in rotation.
The magnetic lines induced by the magnetic bar 74 and the silicon steel 75 are centrally located on a same plane. Only the radial direction of the magnetic lines contributes to the rotation of the rotor 72, while the weight load is principally supported by the surface where the axle 70 and the bearing 72 come into contact with each other. Therefore, the rotor 72 easily slants toward the stator 73. When the motor 7 rotates, the rotor 72 deviates from its normal path and wears away the bearing 7 in a radial direction. Consequently, the bearing 7 becomes elliptic or irregular, which increases the friction coefficient, and causes erratic running of the motor, a louder mechanic noise and a shorter service life. Furthermore, the type of conventional heat-dissipating fan is not suitable for use in portable products that are usually used in different positions and orientations.